Research interests

  • Dialog management: Applications of machine learning; integration of expert knowledge; multi-modal dialog management; planning techniques; on-line improvement.
  • Dialog and user modeling: Tracking and quantifying uncertainty in dialog state for human/computer dialog; representational structures for dialog state; ontology integration; simulation.
  • Turn-taking: Use of continuous/incremental speech recognition for turn-taking; integration of conversation history and user model for turn-taking.
  • Confidence scoring: Machine-learning-based approaches to confidence scoring; calibration in confidence scoring; features for confidence scoring.
  • Planning under uncertainty: Markov decision processes (MDPs); partially observable Markov decision processes (POMDPs); reinforcement learning.
  • Deep learning: Methods for modeling dialog and implementing dialog control using deep learning, particularly recurrent neural networks.

Recent projects

  • Hybrid Code Networks: End-to-end learning for dialog systems that support domain knowledge in the form of software (code) and action templates. [video, paper, demo description]
  • Language Understanding Intelligent Service (LUIS): LUIS is a new, fast way of building language understanding models. LUIS is available at luis.ai.
  • Dialog Systems Technology Challenge (DSTC — originally Dialog State Tracking Challenge): An on-going series of research community challenge tasks related to dialog systems and dialog state tracking. DSTC homepage.


  • Microsoft Research, Principal Researcher, 2012-Present
  • AT&T Labs Research, Principal Member of Technical Staff, 2006-2012
  • Cambridge University, Ph D, Engineering Dept, 2002-2006
  • Edify Corp, Senior consultant – Usability and Speech Technology, 2002-2005
  • Tellme Networks, Voice Application Development Manager, 2000-2001
  • McKinsey & Company, Associate, 1999-2000
  • Cambridge University, Masters, Speech/Language Processing, 1998-1999
  • Princeton University, BSE, Electrical Engineering, 1994-1998


Interns (current and former)

Kavosh Asadi, Summer 2016 and 2017.
Reinforcement learning with recurrent neural networks for dialog systems.
Currently a PhD student with Michael Littman, Brown University.

Hao Fang, Summer 2015.
Natural language understanding.
Currently a PhD student with Mari Ostendorf, University of Washington.

Nobal Niraula, Summer 2014.
Natural language understanding.
Currently with Boeing Research & Technology.

Pradeep Dasigi, Summer 2014.
Conversational systems.
Currently a PhD student with Ed Hovy, CMU.

Ke Zhai, Summer 2013.
Dialog modeling.
Currently an Applied Scientist at Microsoft.

He He, Summer 2013.
Action selection in dialog systems (co-mentored with Lihong Li as lead mentor).
Currently a post-doc researcher with Percy Liang at Stanford University.

Angeliki Metallinou, Summer 2012.
Belief tracking in dialog systems (co-mentored with Dan Bohus).
Currently a Speech Scientist at Amazon.

Ethan Selfridge, Summer 2010 and 2011 at AT&T.
Turn-taking in dialog systems.
Currently at Interactions Corp.

Hamid Chinaei, Summer 2010 at AT&T.
Reinforcement learning for dialog systems.
Currently with Nuance Communications.

John Asmuth, Summer 2009 at AT&T.
Bayesian approaches to reinforcement learning.
Currently at Google.

Lihong Li, Summer 2008 at AT&T.
Feature selection in reinforcement learning.
Currently a Researcher with Microsoft Research.

Umar Syed, Summer 2007 at AT&T.
Learning user models from unlabeled data.
Currently a research scientist at Google.

Thesis committees

Ethan Selfridge, Oregon Health & Science University (2013)
Rohit Kumar, Carnegie Mellon University (2011).


8010364: System and method for applying probability distribution models to dialog systems in the troubleshooting domain

8140328: User intention based on N-best list of recognition hypotheses for utterances in a dialog

8433578: System and method for automatically generating a dialog manager

8457968: System and method for efficient tracking of multiple dialog states with incremental recombination

8473292: System and method for generating user models from transcribed dialogs

8660844: System and method of evaluating user simulations in a spoken dialog system with a diversion metric

8914288: System and method for advanced turn-taking for interactive spoken dialog systems

8954319: System and method for generating manually designed and automatically optimized spoken dialog systems

9015048: Incremental speech recognition for dialog systems

9547471: Generating computer responses to social conversational inputs

[ + 8 more patent applications in progress with the US Patent Office ]

Appointments, editor, and organizer roles

Journal reviewing and grant panelist

Conference program committees

Workshop and other program committees

  • ACL demo committee: 2011.
  • ACL Student Research workshop program committee: 2014, 2015.
  • COLING Demonstration session: 2016, 2014.
  • COLING Workshop: Spoken language technologies for pervasive speech-based and multimodal applications program committee: 2014, 2008
  • Workshop on Speech-centric Natural Language Processing, program committee: 2017 (EMNLP), 2016 (COLING)
  • DSTC workshop, reviewer: 2017.
  • Domain Adaptation for Dialog Agents Workshop (DADA): 2016
  • EACL 2014 Workshop on Dialog in Motion: 2014.
  • ECAI/IJCAI/AAAI Workshop on Machine Learning for Interactive Systems (MLIS): 2015, 2014, 2013, 2012
  • EMNLP Workshop on Modeling Large Scale Social Interaction in Massively Open Online Courses: 2014.
  • Future and Emerging Trends in Language Technologies (FELT): 2015, 2016.
  • ICML Workshop on Learning to Generate Natural Language: 2017.
  • IJCAI Workshop on Knowledge and Reasoning in Practical Dialogue Systems program committee: 2011, 2009.
  • Machine Learning for Spoken Language Understanding and Interactions Workshop (at NIPS): 2015.
  • NAACL Student Research workshop program committee: 2015.
  • NIPS Workshop on Learning Semantics: 2014.
  • NIPS Conversational Intelligence Challenge: 2017.
  • RE-WOCHAT (Workshop on Collecting and Generating Resources for Chatbots and Conversational Agents – Development and Evaluation): 2016 (1), 2016 (2)
  • SLAM: Joint ISCA/IEEE International Workshop on Speech, Language and Audio in Multimedia: 2013.
  • Workshop on Future and Emerging Trends in Language Technology: 2015.
  • Workshop on Future directions and needs in the Spoken Dialog Community: Tools and Data scientific committee: 2012.
  • Workshop on Speech-Centric Natural Language Processing: 2017 2016 –>
  • Young researchers’ roundtable on spoken dialogue systems advisory board: 2018, 2016, 2015, 2014, 2013, 2012, 2011, 2010, 2009, 2006.





Language Understanding Intelligent Service (LUIS)

LUIS is a new, fast way of building language understanding models.  LUIS is available at luis.ai.


Dialog State Tracking Challenge

The Dialog State Tracking Challenge (DSTC) is a research community challenge task for accurately estimating a user’s goal in a spoken dialog system. DSTC homepage.